The phosphate polyanionic Na₄Fe₃(PO₄)₂(P₂O₇) cathode material stands out among many sodium ion battery cathode materials due to its stable structure, high safety and excellent sodium storage performance. However, the unsatisfactory conductivity and energy density limit its application. In this paper, the Na₄Fe₃(PO₄)₂(P₂O₇) cathode material is doped with B element. The small-sized BO₃³-doping replaces the PO₄³-in the NFPP material will cause local lattice shrinkage, which can buffer the volume change during charging and discharging. The stability of the three-dimensional framework is optimized, thereby improving the electrochemical performance of the material. The results show that the appropriate amount of B doping can improve the reversible specific capacity of Na₄Fe₃(PO₄)₂(P₂O₇) material, and improve the rate performance and cycle performance of the material. The NFPP-B0.05/C material has the best electrochemical performance, and the discharge specific capacity reaches 100.9 mAh g^-1 at 0.2 C. At an ultra-high rate of 20 C, the discharge specific capacity of 84.1 mAh g^-1 is still maintained, and the capacity retention rate is 92.6% after 1000 cycles at a high rate of 5 C.

Huayu Feng, Tingjun Song, Xinrui Xiao, Ling Chen. Preparation and Electrochemical Properties of B-Doped Na₄Fe₃(PO₄)₂(P₂O₇) Materials. Academic Journal of Materials & Chemistry (2025), Vol. 6, Issue 3: 30-37. https://doi.org/10.25236/AJMC.2025.060303.

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